1) Field of the Invention
The present invention relates generally to hydraulically driven implements and, more specifically, to structure for selectively engaging and disengaging hydraulic wheel motors for such implements.
2) Related Art
Hydraulic wheel motors are commonly used in implements such as agricultural sprayers to provide good drive characteristics and facilitate wheel tread adjustments for varying row spacings. The drive arrangement requires that the wheel motor drive be disconnected from the reduction gear to avoid damage to the hydrostatic system during towing of the implement. If the operator fails to disconnect the drive, the reduction gear drives the hydraulic motor at a high rate of rotation, and the motor can be damaged after being towed only a relatively short distance. Present disconnect systems, an example of which is shown in FIG. 1, typically include a reversible cap having a drive position wherein an axially movable, spring-loaded splined drive shaft is released and extends into driving connection with a planetary gear structure in the hub. The cap has a depressor which, when the cap is reversed, urges the splined drive shaft away from driving relationship with the reduction gear. Reversible cap arrangements are inconvenient and time consuming to operate. Other types of systems relying on detents become sticky and undependable after operating in the severe agricultural environment.